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Insulin Producing E. coli
Humulin Humulin is the brand name for a group of biosynthesized human insulin products. Synthesis of Humulin uses a laboratory strain of Escherichia coli that has been treated with recombinant DNA. Humulin was first developed in 1978 by Arthur Riggs, while he was working with Genentech. The rights to Humulin were later acquired by Eli Lilly and Company who facilitated the approval of the product with the United State's Food and Drug Administration. Humulin is structurally and chemically identical to human insulin, and is sold by Eli Lilly and Company in a variety of forms, all of which are developed using recombinant DNA. * Humulin R- a short-acting insulin that has a shorter duration of activity compared to most insulins. * Humulin R Regular U-500- a more concentrated version of Humulin R (500 units/mL). * Humulin N- is an intermediate acting insulin with a slower onset of action and longer duration of activity than Humulin R. * Humulin 70/30 (70% human insulin isophane suspension and 30% human insulin injection)- has an intermediate duration of action, and combined with the same onset of action as Humulin R. * Humulin 50/50 (50% human insulin isophane suspension and 50% human insulin injection)- this is an intermediate acting insulin combined with the onset of action the same as Humulin R. Synthesis of Human Insulin using E. coli Synthetic genes for human insulin chains A and B are cloned into plasmid pBR322. Chain A and Chain B are both cloned separately. The synthetic A and B chains are then fused into the E. coli beta-galactosidase gene in order to ensure efficient transcription and translation as well as a precursor protein. The separate insulin peptides are then cleaved from the beta-galactosidase gene, detected by radioimmunoassay, and then purified. The purified products are then mixed, reduced, and reoxidized. The presence of insulin can then be detected by radioimmunoassay. History of Insulin Production Until the 1980s insulin was produced by isolating it from animal pancreases. Animals that were used include pigs, cows, and horses. Approximately 2 tons of pig pancreas was needed to produce only 8 ounces of purified insulin. This was not the only disadvantage to this means of insulin production. Even though pig insulin only differs from human insulin by only 1 amino acid and bovine insulin by only 3 amino acids, some individuals would still respond to the animal insulin as foriegn. This would lead to an immune response and decreased potency over time. In the 1980's Eli Lilly and Company began producing insulin using E. coli. This new means of insulin production was a cheaper method, and produced insulin that was chemically and structurally identical to human insulin. In terms of streamlining and decreasing cost of insulin production Eli Lilly and company completely succeeded by using recombinant DNA technology and transgenic E.coli. References Goeddel, D. V. "Expression in Escherichia Coli of Chemically Synthesized Genes for Human Insulin." Expression in Escherichia Coli of Chemically Synthesized Genes for Human Insulin. Proceeding of the National Academy of Sciences for the United States of America, n.d. Web. 06 Oct. 2014. . "Humulin." Wikipedia. Wikimedia Foundation, 24 Aug. 2014. Web. 06 Oct. 2014. . Gebel, Erika. "Making Insulin." Diabetes Forecast. American Diabetes Association, 2013. Web. 05 Oct. 2014. .